Altronix EFLOW4NB 12/24VDC Battery-Backed Power Supply
The EFLOW4NB is a UL Listed single-output power supply that delivers 12/24VDC at 4A continuous, making it a workhorse for access control, alarm systems, and distributed security infrastructure. It accepts standard 120VAC 60Hz input (6A maximum draw) and includes integrated battery backup with automatic AC-loss switchover—essential when your door locks, intrusion panels, or auxiliary cameras cannot afford downtime. The voltage output is selectable via DIP switch (12V or 24V), so you won't need separate SKUs for different deployments.
Key Features
- Selectable 12/24VDC output via DIP switch: Eliminates inventory overhead and simplifies field swaps when endpoint voltage requirements vary across your integration.
- 4A continuous output: Sufficient for a single access control door lock, backup power for a compact intrusion panel, or auxiliary circuits in a distributed PoE camera setup. Verify your endpoint spec sheet to confirm this doesn't oversubscribe on your load.
- Integrated battery backup with automatic switchover: On AC mains loss, the supply holds over to battery power without manual intervention—critical for access control failover and emergency egress scenarios. Your downstream devices remain powered during an outage until battery depletion.
- Fire alarm disconnect circuit: Isolates the supply from battery when the fire alarm system signals—a code requirement in many jurisdictions. Verify your local Authority Having Jurisdiction (AHJ) mandate before final design.
- AC Fail, Low Battery, and Battery Presence supervision signals: These dry-contact outputs allow your security panel or remote monitoring station to track power health in real time. Use them to trigger alerts or log outage events.
- Single output with dedicated auxiliary terminal: Accommodates both primary load and a secondary auxiliary circuit; useful for supplementary sensors or signaling without a second supply.
- UL Listed: Meets Underwriters Laboratories safety standards, permitting direct integration into certified security systems without additional redundant testing.
Integration & Compatibility
The EFLOW4NB is designed to sit within a standard system cabinet or DIN-rail enclosure. It accepts 120VAC mains from a dedicated 20A circuit breaker (sized for the 6A input draw plus margin). Supervision outputs (AC Fail, Low Battery, Battery Presence) wire to your control panel's input terminals—consult your panel's wiring diagram for signal interpretation (typically dry-contact closure). The battery itself is sold separately; confirm capacity with Altronix technical documentation or your system integrator based on your load profile and required backup runtime (e.g., 1 hour, 4 hours, 24 hours).
If you are deploying power supplies across an enterprise network of access control points, confirm that your cabinet layout supports wall or DIN-rail mounting and that your panel supports supervised power input supervision. For warehouse or retail environments with multiple doors, you may deploy multiple EFLOW4NB units in parallel enclosures, each protecting a separate door lock or alarm circuit.
When to Choose a Different Model
If you require higher continuous current (e.g., 8A or 12A for a larger panel or multiple locks), evaluate higher-amperage variants from the Altronix power supply line. If your load does not require battery backup, a non-backed supply may reduce cost and footprint. If you need multiple independent outputs (e.g., separate 12V and 24V rails), consider a dual-output power supply in the same family.
Frequently Asked Questions
Q: What battery type does the EFLOW4NB support?
A: The supply integrates battery backup capability but does not include the battery itself. Confirm battery type and capacity compatibility with your Altronix distributor or the product datasheet (typically 12V sealed lead-acid; consult documentation for amp-hour recommendations based on your load and runtime target).
Q: Can I operate the EFLOW4NB in a non-air-conditioned cabinet?
A: Yes, but monitor ambient temperature. Battery and power electronics degrade faster at elevated temperatures. Refer to the operating temperature range in the product datasheet and size your enclosure ventilation accordingly.
Q: Does the fire alarm disconnect circuit require additional wiring?
A: The circuit is built in. It activates on a fire alarm signal (typically from your panel's fire loop). Confirm your panel sends the correct signal type (dry-contact, voltage pulse) and verify local fire code requirements with your AHJ.
Q: How do I know when the battery is low?
A: The EFLOW4NB provides a dedicated Low Battery supervision output. Wire this to your security panel's input terminal so you receive an alarm condition and can trigger maintenance or replacement before full depletion.
Q: Is the EFLOW4NB suitable for outdoor cabinet use?
A: The supply itself is not outdoor-rated (no IP rating). Deploy it inside a weatherproof cabinet (NEMA 4X or equivalent) and route 120VAC mains through a weatherproof disconnect switch. Verify your local electrical code for outdoor cabinet requirements.
Q: What does the Battery Presence supervision signal do?
A: This dry-contact output confirms that a battery is physically connected. Use it to alert technicians if a battery becomes disconnected or fails; prevents silent failures where backup power is unavailable during an outage.
Ted PerryPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
The EFLOW4NB is a compact, field-proven choice for single-door or small multi-circuit access control backup. At 4A continuous output, it delivers sufficient headroom for most electromagnetic locks and compact alarm panels without undersizing risk. The selectable 12/24VDC output eliminates procurement delays when your endpoint specs vary—a time-saver in mixed-voltage environments.
Technical Highlights:
- 6A maximum input draw: Keeps the supply on a standard 20A dedicated branch circuit with comfortable safety margin, simplifying electrical planning and reducing the likelihood of nuisance breaker trips during inrush.
- AC Fail, Low Battery, and Battery Presence supervision: Three independent dry-contact outputs allow your security panel to detect mains failure, low battery state, and battery disconnection—critical for 24/7 monitoring. This granular feedback prevents silent power failures that would otherwise go undetected until the next manual inspection.
- Integrated fire alarm disconnect: Meets code in jurisdictions requiring automatic battery isolation during fire alarm activation. Built-in prevents forgotten wiring during retrofit installations.
Deployment Considerations:
- Battery is not included; capacity must match your runtime requirement (1, 4, 8, or 24 hours). Undersizing the battery defeats the backup purpose; oversizing increases cost and enclosure footprint. Work with your integrator to calculate load current and verify battery amp-hour rating.
- The 4A limit is the binding constraint. If you are driving two access control locks in parallel (typical 500–700mA each), you will consume ~1.5A. Add an auxiliary camera power draw or a high-draw solenoid, and you risk exceeding the supply's capacity. Always sum your endpoint currents before finalizing the design.
- Supervision outputs are dry-contact, not powered relay outputs. They signal state changes to a security panel input, not directly to external devices. Confirm your panel supports supervised power input before wiring.
The EFLOW4NB is best suited to single-circuit deployments—one secure door, one small intrusion panel, or a hybrid of low-current auxiliary loads. In larger multi-door warehouses or retail chains, you'll deploy multiple units in parallel enclosures, each protecting independent circuits. For high-current centralized backup (>4A), step up to a higher-amperage model in the Altronix family.
